DESCRIPTION

These functions are glibc-specific.
An argz vector is a pointer to a character buffer together with a
length. The intended interpretation of the character buffer is an
array of strings, where the strings are separated by null bytes ('\0').
If the length is nonzero, the last byte of the buffer must be a null
byte.
These functions are for handling argz vectors. The pair (NULL,0) is an
argz vector, and, conversely, argz vectors of length 0 must have NULL
pointer. Allocation of nonempty argz vectors is done using malloc(3),
so that free(3) can be used to dispose of them again.
argz_add() adds the string str at the end of the array *argz, and
updates *argz and *argz_len.
argz_add_sep() is similar, but splits the string str into substrings
separated by the delimiter delim. For example, one might use this on a
Unix search path with delimiter ':'.
argz_append() appends the argz vector (buf, buf_len) after
(*argz, *argz_len) and updates *argz and *argz_len. (Thus, *argz_len
will be increased by buf_len.)
argz_count() counts the number of strings, that is, the number of null
bytes ('\0'), in (argz, argz_len).
argz_create() converts a Unix-style argument vector argv, terminated by
(char*)0, into an argz vector (*argz, *argz_len).
argz_create_sep() converts the null-terminated string str into an argz
vector (*argz, *argz_len) by breaking it up at every occurrence of the
separator sep.
argz_delete() removes the substring pointed to by entry from the argz
vector (*argz, *argz_len) and updates *argz and *argz_len.
argz_extract() is the opposite of argz_create(). It takes the argz
vector (argz, argz_len) and fills the array starting at argv with
pointers to the substrings, and a final NULL, making a Unix-style argv
vector. The array argv must have room for argz_count(argz,argz_len) +
1 pointers.
argz_insert() is the opposite of argz_delete(). It inserts the
argument entry at position before into the argz vector
(*argz, *argz_len) and updates *argz and *argz_len. If before is NULL,
then entry will inserted at the end.
argz_next() is a function to step trough the argz vector. If entry is
NULL, the first entry is returned. Otherwise, the entry following is
returned. It returns NULL if there is no following entry.
argz_replace() replaces each occurrence of str with with, reallocating
argz as necessary. If replace_count is non-NULL, *replace_count will
be incremented by the number of replacements.
argz_stringify() is the opposite of argz_create_sep(). It transforms
the argz vector into a normal string by replacing all null bytes ('\0')
except the last by sep.

RETURNVALUE

All argz functions that do memory allocation have a return type of
error_t, and return 0 for success, and ENOMEM if an allocation error
occurs.

CONFORMINGTO

These functions are a GNU extension. Handle with care.

BUGS

Argz vectors without a terminating null byte may lead to Segmentation
Faults.